阅读说明：本技术 一种基于飞轮储能的机械蓄能电梯系统 (Mechanical energy storage elevator system based on flywheel energy storage ) 是由 熊焰 冯程 邓家炜 吴锡森 姚志伟 于 2021-10-15 设计创作，主要内容包括：本发明公开了一种基于飞轮储能的机械蓄能电梯系统,该系统包括承载组件和驱动承载组件上行或下行的动力组件；承载组件包括轿厢和对重；动力组件包括曳引绳、导向轮、驱动轮、变速箱、电机和飞轮；曳引绳绕设在驱动轮和导向轮上,且两端分别连接着轿厢和对重；电机通过变速箱与驱动轮连接,且通过变速箱将动力传递给驱动轮；飞轮通过变速箱与驱动轮连接,且通过变速箱接收并储存驱动轮的机械能。本发明通过利用飞轮储能,能够回收电梯空载上行和满载下行的重力势能,不仅解决了电梯电储能带来的消防和安全问题,而且还避免了电梯能量反馈和谐波对电网的冲击,提高了能源利用效率,降低了电梯能耗,从而降低了建筑耗能。(The invention discloses a mechanical energy storage elevator system based on flywheel energy storage, which comprises a bearing component and a power component for driving the bearing component to move upwards or downwards; the bearing assembly comprises a car and a counterweight; the power assembly comprises a hauling rope, a guide wheel, a driving wheel, a gearbox, a motor and a flywheel; the traction rope is wound on the driving wheel and the guide wheel, and two ends of the traction rope are respectively connected with the car and the counterweight; the motor is connected with the driving wheel through the gearbox, and transmits power to the driving wheel through the gearbox; the flywheel is connected with the driving wheel through the gearbox, and receives and stores mechanical energy of the driving wheel through the gearbox. The invention can recover the gravitational potential energy of the elevator in no-load ascending and full-load descending by utilizing the energy storage of the flywheel, thereby not only solving the fire control and safety problems caused by the electric energy storage of the elevator, but also avoiding the impact of the energy feedback and harmonic waves of the elevator on a power grid, improving the energy utilization efficiency, reducing the energy consumption of the elevator and further reducing the energy consumption of buildings.)

1. A mechanical energy storage elevator system based on flywheel energy storage is characterized by comprising a bearing assembly and a power assembly for driving the bearing assembly to move upwards or downwards; wherein the content of the first and second substances,

the load bearing assembly comprises a car and a counterweight;

the power assembly comprises a traction rope, a guide wheel, a driving wheel, a gearbox, a motor and a flywheel;

the traction rope is wound on the driving wheel and the guide wheel, and two ends of the traction rope are respectively connected with the car and the counterweight;

the motor is connected with the driving wheel through the gearbox, and power is transmitted to the driving wheel through the gearbox;

the flywheel is connected with the driving wheel through the gearbox, and receives and stores mechanical energy of the driving wheel through the gearbox.

2. The flywheel energy storage based mechanical energy storage elevator system of claim 1, wherein the gearbox comprises a drive shaft, a backup roller bearing, a clutch, an energy storage shaft, a drive shaft, a forward synchronizer, a forward gear, a clutch sleeve, a splined hub, a reverse synchronizer, a reverse gear, and an idler shaft;

one end of the driving shaft is connected with the motor through the clutch, and the other end of the driving shaft is connected with the driving wheel;

one end of the energy storage shaft is connected with the flywheel through the other clutch;

the forward synchronizer, the forward gear, the reverse synchronizer and the reverse gear are respectively assembled on the transmission shaft;

the spline hub is fixed on the transmission shaft, is positioned between the forward synchronizer and the reverse synchronizer and is meshed with the joint sleeve;

the driving shaft, the energy storage shaft, the transmission shaft and the idler shaft are all sleeved with the supporting roller bearing.

3. The flywheel energy storage based mechanical energy storage elevator system of claim 1, wherein the gearbox further comprises a housing;

the driving shaft, the supporting roller bearing, the energy storage shaft, the transmission shaft, the forward synchronizer, the forward gear, the joint sleeve, the spline hub, the reverse synchronizer, the reverse gear and the idler shaft are all arranged in the shell;

the clutch is disposed outside the housing.

4. The mechanical energy storage elevator system based on flywheel energy storage of claim 1, characterized in that the guide wheel is located on a side near the counterweight and the drive wheel is located on a side near the car.

5. The mechanical energy storage elevator system based on flywheel energy storage of claim 1, characterized in that the guide wheels are disposed at the same height as the driving wheels.

6. The mechanical energy storage elevator system based on flywheel energy storage of claim 1, characterized in that the flywheel is a magnetic levitation flywheel.

7. The mechanical energy storage elevator system based on flywheel energy storage of claim 1, characterized in that the flywheel is disposed within a vacuum chamber.

Technical Field

The invention relates to the technical field of elevators, in particular to a mechanical energy storage elevator system based on flywheel energy storage.

Background

With the continuous acceleration of the urbanization process in China, urban population is more and more, and occupied area per capita is less and less, so that high-rise buildings are continuously emerging and rapidly become the main form of urban buildings.

Elevators are commonly used for taking people or carrying goods in high-rise buildings as vertical transportation vehicles with complex structures. In life, an elevator is convenient and fast for people and is indispensable, however, while the elevator is widely popularized and developed, the energy consumption of the elevator is also increased at an incredible speed, and then along with the increasing prominence of energy problems, the energy-saving technology of the elevator becomes one of the topics concerned by people.

It is known that during operation of an elevator the motor has two operating states, i.e. a motor state and a generator state. Under some elevator load conditions, such as an empty-load descending elevator or an empty-load ascending elevator, the motor needs to overcome a certain resistance to pull the car and the counterweight of the elevator, and at the moment, the motor can draw and consume electric energy from a power grid (a control cabinet) and is in a motor state; in other load situations, such as an empty up-going elevator or a full down-going elevator, the empty car will naturally go up or the full car will naturally go down under the action of gravity due to the unbalanced weight between the car and the counterweight side, and the motor is in a generator state without power.

At present, when a motor is in a generator state, the traditional elevator consumes the energy by using an energy consumption resistor, so that energy waste is caused, and internal energy is increased, thereby increasing the cooling load of machine room heat dissipation. In order to solve the problem, in the prior art, mechanical energy of an elevator is converted into electric energy through a motor and fed back to a power grid in real time to realize energy recovery, but unstable generated power and harmonic have large impact on the power grid, so that the recovery rate is low. Later, in the prior art, the generated energy of the motor is stored by an electrochemical or capacitive energy storage method and then is recycled, so that energy recovery is achieved, and impact on a power grid is avoided, but the electrical energy storage has the defects of flammability, explosiveness, high cost and the like, and the gravitational potential energy of the elevator is subjected to energy conversion loss through each stage of conversion (mechanical energy → electric energy → electrochemical energy storage → electric energy → mechanical energy), so that the method is not an optimal elevator energy recovery means.

Therefore, there is a need for improvements in the prior art.

The above information is given as background information only to aid in understanding the present disclosure, and no determination or admission is made as to whether any of the above is available as prior art against the present disclosure.

Disclosure of Invention

The invention provides a mechanical energy storage elevator system based on flywheel energy storage, which aims to overcome the defects in the prior art.

In order to achieve the above purpose, the present invention provides the following technical solutions:

a mechanical energy storage elevator system based on flywheel energy storage comprises a bearing assembly and a power assembly for driving the bearing assembly to move upwards or downwards; wherein the content of the first and second substances,

the load bearing assembly comprises a car and a counterweight;

the power assembly comprises a traction rope, a guide wheel, a driving wheel, a gearbox, a motor and a flywheel;

the traction rope is wound on the driving wheel and the guide wheel, and two ends of the traction rope are respectively connected with the car and the counterweight;

the motor is connected with the driving wheel through the gearbox, and power is transmitted to the driving wheel through the gearbox;

the flywheel is connected with the driving wheel through the gearbox, and receives and stores mechanical energy of the driving wheel through the gearbox.

Further, in the mechanical energy storage elevator system based on flywheel energy storage, the gearbox comprises a driving shaft, a supporting roller bearing, a clutch, an energy storage shaft, a transmission shaft, a forward synchronizer, a forward gear, a joint sleeve, a spline hub, a reverse synchronizer, a reverse gear and an idler shaft;

one end of the driving shaft is connected with the motor through the clutch, and the other end of the driving shaft is connected with the driving wheel;

one end of the energy storage shaft is connected with the flywheel through the other clutch;

the forward synchronizer, the forward gear, the reverse synchronizer and the reverse gear are respectively assembled on the transmission shaft;

the spline hub is fixed on the transmission shaft, is positioned between the forward synchronizer and the reverse synchronizer and is meshed with the joint sleeve;

the driving shaft, the energy storage shaft, the transmission shaft and the idler shaft are all sleeved with the supporting roller bearing.

Further, in the mechanical energy storage elevator system based on flywheel energy storage, the gearbox further comprises a shell;

the driving shaft, the supporting roller bearing, the energy storage shaft, the transmission shaft, the forward synchronizer, the forward gear, the joint sleeve, the spline hub, the reverse synchronizer, the reverse gear and the idler shaft are all arranged in the shell;

the clutch is disposed outside the housing.

Further, in the mechanical energy storage elevator system based on flywheel energy storage, the guide wheel is positioned on one side close to the counterweight, and the driving wheel is positioned on one side close to the car.

Furthermore, in the mechanical energy storage elevator system based on flywheel energy storage, the guide wheels and the driving wheels are arranged at the same height.

Further, in the mechanical energy storage elevator system based on flywheel energy storage, the flywheel is a magnetic suspension flywheel.

Further, in the mechanical energy storage elevator system based on flywheel energy storage, the flywheel is arranged in the vacuum chamber.

Compared with the prior art, the embodiment of the invention has the following beneficial effects:

according to the mechanical energy storage elevator system based on flywheel energy storage, the flywheel energy storage is utilized, the gravitational potential energy of the elevator in no-load ascending and full-load descending can be recovered, the fire fighting and safety problems caused by elevator electric energy storage are solved, the impact of elevator energy feedback and harmonic waves on a power grid is avoided, the energy utilization efficiency is improved, the energy consumption of the elevator is reduced, and therefore the building energy consumption is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a mechanical energy storage elevator system based on flywheel energy storage according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a transmission provided in an embodiment of the present invention;

FIG. 3 is a schematic diagram of the movement directions of the components during ascending with no energy charging or ascending with full energy discharging according to the embodiment of the present invention;

fig. 4 is a schematic diagram of the movement directions of the components during full-load descending or no-load descending of the energy charging system according to the embodiment of the invention.

Reference numerals:

the elevator comprises a car 1, a counterweight 2, a traction rope 3, a guide wheel 4, a driving wheel 5, a gearbox 6, a motor 7 and a flywheel 8;

the transmission comprises a housing 601, a driving shaft 602, a support roller bearing 603, a clutch 604, an energy storage shaft 605, a transmission shaft 606, a forward synchronizer 607, a forward gear 608, a joint sleeve 609, a spline hub 610, a reverse synchronizer 611, a reverse gear 612 and an idler shaft 613.

Detailed Description

In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the embodiments described below are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present.

Furthermore, the terms "long", "short", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the present invention, but do not indicate or imply that the referred devices or elements must have the specific orientations, be configured to operate in the specific orientations, and thus are not to be construed as limitations of the present invention.

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

Example one

In view of the above-mentioned defects of the existing elevator energy recovery technology, the applicant of the present invention is based on practical experience and professional knowledge that are abundant years after the industry is designed and manufactured, and is matched with the application of theory to actively make research and innovation, so as to hopefully create a technology capable of solving the defects in the prior art, so that the elevator energy recovery technology has higher practicability. After continuous research and design and repeated trial production and improvement, the invention with practical value is finally created.

Referring to fig. 1 to 2, an embodiment of the present invention provides a mechanical energy storage elevator system based on flywheel 8 energy storage, where the system includes a load bearing assembly and a power assembly driving the load bearing assembly to move up or down; wherein the content of the first and second substances,

the bearing assembly comprises a car 1 and a counterweight 2; the car 1 is used for transporting passengers and goods; the counterweight 2 is used for balancing the self weight and a part of the load weight of the car 1.

The power assembly comprises a traction rope 3, a guide wheel 4, a driving wheel 5, a gearbox 6, a motor 7 and a flywheel 8;

the traction rope 3 is wound on the driving wheel 5 and the guide wheel 4, and two ends of the traction rope are respectively connected with the car 1 and the counterweight 2; the guide wheel 4 is positioned at one side close to the counterweight 2, and the driving wheel 5 is positioned at one side close to the car 1 and is arranged at the same height; the guide wheel 4 is used for pulling the distance of the hoisting rope 3 on two sides of the driving wheel 5, so that the hoisting rope 3 vertically acts on the counterweight 2 and the car 1; the driving pulley 5 is used for transmitting power generated by the motor 7 to the hoist rope 3, and the car 1 is driven to ascend or descend by means of friction force between the hoist rope 3 and the rope groove of the driving pulley 5.

The motor 7 is connected with the driving wheel 5 through the gearbox 6, and transmits power converted from electric energy to the driving wheel 5 through the gearbox 6;

the flywheel 8 is connected with the driving wheel 5 through the gearbox 6, and receives and stores the mechanical energy of the driving wheel 5 through the gearbox 6; specifically, the gearbox 6 transmits the mechanical energy of the driving wheel 5 to the flywheel 8, and at the moment, the flywheel 8 stores energy and the rotating speed is increased; when releasing energy, the bearings of the flywheel 8 do work outwards, i.e. the mechanical energy is transmitted back to the driving wheel 5 again, and the rotating speed is reduced.

In order to reduce air resistance and energy loss, it is preferable that the flywheel 8 is a magnetic suspension flywheel, or the flywheel 8 is disposed in a vacuum chamber.

It should be noted that other designs of the elevator system, such as safety protection, electrical control, door system, trailing cable, etc. of the elevator, are specifically used to ensure that the functions of the elevator system work properly, and as these designs are implemented in the prior art and are not the main point of the design of the present solution, they are not further described here.

In the present embodiment, as shown in fig. 2, the transmission 6 includes a driving shaft 602, a support roller bearing 603, a clutch 604, an energy storage shaft 605, a transmission shaft 606, a forward synchronizer 607, a forward gear 608, a coupling sleeve 609, a spline hub 610, a reverse synchronizer 611, a reverse gear 612, and an idler shaft 613;

one end of the driving shaft 602 is connected with the motor 7 through a clutch 604, and the other end is connected with the driving wheel 5;

one end of the energy storage shaft 605 is connected with the flywheel 8 through another clutch 604; the clutch 604 connected to the motor 7 or the clutch 604 connected to the flywheel 8 is closed when applying work, and is separated when not applying work, so as to control the connection of the motor 7 or the flywheel 8 and reduce the impact of a shaft wheel when starting the connection.

The forward synchronizer 607, the forward gear 608, the reverse synchronizer 611 and the reverse gear 612 are respectively assembled on the transmission shaft 606; the forward synchronizer 607 synchronously rotates the forward gear 608 and the transmission shaft 606, and particularly, when the forward synchronizer 607 is pressed against the forward gear 608, the forward gear 608 and the transmission shaft 606 can synchronously rotate through friction force. The forward gear 608 transfers the torque of the drive shaft 606 to the drive shaft 602.

The spline hub 610 is fixed on the transmission shaft 606, and is located between the forward synchronizer 607 and the reverse synchronizer 611, and is engaged with the engaging sleeve 609; the engaging sleeve 609 can be pushed by a direction-changing push rod thereon to move toward the forward synchronizer 607 or the reverse synchronizer 611. When the clutch sleeve 609 is pushed toward the forward synchronizer 607 and presses it against the forward gear 608, torque will be transmitted to the forward gear 608; when the engaging sleeve 609 is pushed towards the reverse synchronizer 611 and presses it against the reverse gear 612, torque will be transmitted to the reverse gear 612.

The reverse synchronizer 611 causes the reverse gear 612 and the transmission shaft 606 to rotate synchronously; the reverse gear 612 is used to transmit the torque of the transmission shaft 606 to the reverse gear 612, the reverse gear 612 is engaged with the idler shaft 613, the idler shaft 613 can maintain the one-way rotation of the flywheel 8, and the idler can change the rotation direction of the driving shaft 602.

The support roller bearings 603 are sleeved on the driving shaft 602, the energy storage shaft 605, the transmission shaft 606 and the idler shaft 613.

Preferably, the gearbox 6 further comprises a housing 601;

the drive shaft 602, the backup roller bearing 603, the energy storage shaft 605, the drive shaft 606, the forward synchronizer 607, the forward gear 608, the engaging sleeve 609, the splined hub 610, the reverse synchronizer 611, the reverse gear 612 and the idler shaft 613 are all arranged in the housing 601;

the clutch 604 is disposed outside the housing 601.

In order to more clearly show the implementation of the embodiments of the present invention, the following detailed description is provided with specific examples.

Energy charging:

as shown in fig. 3, if the car is unloaded and ascends, the gravity of the counterweight 2 is greater than the gravity of the car 1; the driving wheel 5 is driven by gravity to rotate in the direction shown in fig. 3, the clutch 604 connected to the flywheel 8 is closed, and the direction-changing push rod on the engaging sleeve 609 pushes the engaging sleeve 609 towards the forward synchronizer 607. The kinetic energy of the driving wheel 5 is meshed with the forward gear 608 through the gear of the driving shaft 602 to drive the transmission shaft 606, and the torque is transmitted to the energy storage shaft 605, so that the flywheel 8 is driven to rotate and charge energy. The direction of movement of the components is shown by the arrows in fig. 3, where gravitational potential energy is converted to kinetic energy in the flywheel 8.

As shown in fig. 4, if the car is fully loaded and descends, the gravity of the counterweight 2 is less than the gravity of the car 1; the driving wheel 5 is driven by gravity to rotate in the direction shown in fig. 4, the clutch 604 connected to the flywheel 8 is closed, and the direction-changing push rod on the engaging sleeve 609 pushes the engaging sleeve 609 towards the reverse synchronizer 611. The kinetic energy of the driving wheel 5 is engaged with the reverse gear 612 through the gear of the driving shaft 602 and the idle gear 613, so as to drive the transmission shaft 606, transmit the torque to the energy storage shaft 605, and drive the flywheel 8 to rotate and charge energy. The direction of movement of the components is shown by the arrows in fig. 4, where gravitational potential energy is converted to kinetic energy in the flywheel 8.

(II) energy storage:

during energy storage, the clutch 604 is disengaged, and the flywheel 8 stores kinetic energy by means of inertia thereof.

(III) discharging energy:

as shown in fig. 3, if the car is fully loaded and ascends, the gravity of the counterweight 2 is less than the gravity of the car 1; the flywheel 8 drives the gearbox 6 to do work, and the driving wheel 5 rotates according to the direction shown in figure 3. The clutch 604 connected with the flywheel 8 is closed, the clutch 604 connected with the motor 7 is separated, the direction-changing push rod on the engaging sleeve 609 pushes the engaging sleeve 609 to the forward synchronizer 607, and the kinetic energy of the flywheel 8 is transmitted to the driving shaft 602 through the energy storage shaft 605, the transmission shaft 606 and the forward gear 608 to drive the driving wheel 5 to rotate. The direction of movement of the components is shown by the arrows in figure 3. The flywheel 8 does work, and the kinetic energy of the flywheel 8 is converted into the gravitational potential energy of the elevator.

As shown in fig. 4, if the car is unloaded downward at this time, the gravity of the counterweight 2 > the gravity of the car 1. The flywheel 8 drives the gearbox 6 to do work, and the driving wheel 5 rotates according to the direction shown in fig. 4. The clutch 604 connected to the flywheel 8 is closed, the clutch 604 connected to the motor 7 is disengaged, and the direction-changing push rod on the engaging sleeve 609 pushes the engaging sleeve 609 towards the reverse synchronizer 611. The kinetic energy of the flywheel 8 is transmitted to the driving shaft 602 through the energy storage shaft 605, the transmission shaft 606 and the reverse gear 612 after going backward through the idle wheel rotation, and drives the driving wheel 5 to rotate. The direction of movement of the various components is shown by the arrows in figure 4. The flywheel 8 does work, and the kinetic energy of the flywheel 8 is converted into the gravitational potential energy of the elevator.

Because most elevator carries the thing and has conservative traffic characteristic, the load of going upstairs is the load of going downstairs (like the resident elevator number of going upstairs is approximately equal to the number of people of going downstairs) so only need a small amount of electric power with the working electric power that provides power and offset friction loss and do work when special traffic and provide electrical equipment in the elevator, alright realize the low operation energy consumption of energy storage elevator.

When the energy stored in the flywheel 8 is insufficient to provide energy for full-load ascending and no-load ascending, the clutch 604 connected with the motor 7 is closed, and under the supply of commercial power, the motor 7 does work through the gearbox 6 to drive the elevator to run.

Although the terms car, counterweight, hoisting rope, guide wheel, drive wheel, gearbox 6, motor 7, flywheel etc. are used more often in this context, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.

According to the mechanical energy storage elevator system based on flywheel energy storage, the flywheel energy storage is utilized, the gravitational potential energy of the elevator in no-load ascending and full-load descending can be recovered, the fire fighting and safety problems caused by elevator electric energy storage are solved, the impact of elevator energy feedback and harmonic waves on a power grid is avoided, the energy utilization efficiency is improved, the energy consumption of the elevator is reduced, and therefore the building energy consumption is reduced.

The foregoing description of the embodiments has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same elements or features may also vary in many respects. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Example embodiments are provided so that this disclosure will be thorough and will fully convey the scope to those skilled in the art. Numerous details are set forth, such as examples of specific parts, devices, and methods, in order to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In certain example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises" and "comprising" are intended to be inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed and illustrated, unless explicitly indicated as an order of performance. It should also be understood that additional or alternative steps may be employed.

When an element or layer is referred to as being "on" … … "," engaged with "… …", "connected to" or "coupled to" another element or layer, it can be directly on, engaged with, connected to or coupled to the other element or layer, or intervening elements or layers may also be present. In contrast, when an element or layer is referred to as being "directly on … …," "directly engaged with … …," "directly connected to" or "directly coupled to" another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship of elements should be interpreted in a similar manner (e.g., "between … …" and "directly between … …", "adjacent" and "directly adjacent", etc.). As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region or section from another element, component, region or section. Unless clearly indicated by the context, use of terms such as the terms "first," "second," and other numerical values herein does not imply a sequence or order. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

Spatially relative terms, such as "inner," "outer," "below," "… …," "lower," "above," "upper," and the like, may be used herein for ease of description to describe a relationship between one element or feature and one or more other elements or features as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the example term "below … …" can encompass both an orientation of facing upward and downward. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted.